M365EXO-035: No IP allow list in connection filter (MS.EXO.12.1)

Plataforma
Entra ID / M365
Categoría
Advanced Threat Protection
Severidad
High
Pilar de Zero Trust
Applications & Workloads (peso 2)
Fixtures de referencia
3
Cobertura de ramas
Observada: los fixtures prueban los veredictos que ejercitan
Procedencia
baseline

Qué comprueba

SCuBA MS.EXO.12.1 recommends that IP allow lists not be created. Addresses on the connection filter allow list bypass spam filtering, SPF, DKIM, DMARC, and FROM-address enforcement. Any entry on this list is a hole through which an attacker who can send from that address can deliver mail that skips all inbound security controls.

Valor recomendado

Connection filter policy IPAllowList empty for all policies

Remediación

Edit the connection filter policy and remove all entries from the allowed IP address list so no senders bypass spam filtering and authentication checks. If a sender must be allowed to avoid false positives, prefer a narrowly scoped allowed-sender entry over an IP allow list. Verify no custom connection filter policy reintroduces allow-list entries.

Veredictos probados con fixtures

Cada veredicto de esta tabla está probado por un fixture de referencia en la suite de pruebas que valida el módulo. La tabla se deriva de la última ejecución en verde; no puede editarse a mano.

Escenarios de veredicto de M365EXO-035
EscenarioVeredicto esperado
cleanPASS
known-badFAIL
throttledNot Assessed

Mapeos a marcos de referencia

NIST SP 800-53
SC-7, SI-8
CIS M365 Benchmark
2.1.12
MITRE ATT&CK
T1566.001